Clooney was in London for a gala screening of his new film

The London Evening Standard claimed the actor got into a fight early on Friday morning after using the rear exit of the Meza bar to avoid photographers.

In a statement, 44-year-old Clooney said he "did not get into a fight", but was coming to the aid of a woman he believed was being mistreated.

"I won't stand by while someone is being insulted and maligned," he said.

Gala screening

The Hollywood star was in London's West End on Thursday night for a gala screening of his latest film, Good Night, And Good Luck, at the 49th London Film Festival.

The movie - Clooney's second as a director - is set during the early years of broadcast journalism in 1950s America.

A statement from his Los Angeles-based publicist, Stan Rosenfield, said the actor "did not get into a fight with a security guard", but did "get into an argument with someone connected with the movie".

"While it had nothing to do with the paparazzi, it did have everything to do with someone being unkind to a woman.

"While no punches were thrown, George told the person to knock it off," the statement added.

A spokeswoman for Meza said none of its staff were involved in an incident with Clooney, but the actor's British management had hired security guards for the reception.